As teams started spring training workouts across Florida and Arizona, the players' association had a Kansas City Royals scout escorted out of the union's opening training session for unsigned free agents.

About 15 players attended the first day of workouts Wednesday at the union's camp in Bradenton, Florida. Media were barred from the IMG Academy. The scout was told he was not welcome but could set up a session with an individual player at the player's discretion, several people familiar with the situation said. The people spoke on condition of anonymity because no statements were authorized.

More than 90 players remain without agreements among the 166 who exercised their free-agency rights last November, the most sluggish market since the final offseason of collusion in 1987-88.

Union head Tony Clark, who attended the session, said approximately15 more players are likely to arrive at the free-agent camp this week while the remainder of unsigned players seeking jobs work out at their regular offseason facilities.

"When you have the type of numbers we've had of unsigned guys at this juncture, that's cause for concern," Clark said. "It's cause for concern from our end and it's cause for concern from an industry standpoint."

"From my perspective, the last four or five days have been more like a true December free agency. We've gotten a lot of calls from a lot of teams, and we're working through negotiations for players," Boras said.

"The trade winds finally died down and the clubs have reached a point where the opportunities for trades have been limited. Now they turn to the free-agent market."

The number of teams in the midst of rebuilds has increased, leaving fewer spots for high-priced veterans.

Changes to the collective bargaining agreement in November 2016 have caused high-spending teams such as the New York Yankees and Los Angeles Dodgers to cut payroll in an effort to get under the luxury tax threshold.

Prospects have become more prized because of limits on the amount clubs can spend on amateurs, a fixed price that factors into team decisions on when to turn toward youth.

"Having a third of the league not as interested in others as competing and even acknowledging as much publicly is a concern," Clark said.

Major League Baseball's proposed rules changes to speed the pace of play have become caught up in the rancor. MLB Commissioner Rob Manfred has threatened to implement management's proposal of last offseason to install 20-second pitch clocks and institute stricter limits on mound visits.

Management told the union on Jan. 23 it would abandon a pitch clock this year as part of a three-year phase-in of new rules, but players have not yet responded.

MLB is pushing the union to answer this week, and Manfred has said he wants the new rules in place before major league exhibition games start Feb. 23.

Under baseball's labor contract, unilateral playing rules changes can be made with one offseason of advance notice. That means only the stricter rules could be put in place unless there's an agreement.

While MLB could decide to implement just a pitch clock or harsher mound visit limits and not both, severing part of the proposal could trigger a grievance by the union that would leave a decision to arbitrator Mark Irvings.